Epirubicin (EPI) is an anti-tumor anthracycline antibiotic, which was semisynthesized by the Italian Scientists Arcamone, et al in 1975. The difference between epirubicin and adriamycin only resides in that the hydroxyl at 4-position of glycosamine moiety is changed from cis-form to trans-form. However, such a small change in stereochemistry results in significant reduction in toxicity on heart and marrow.
The main action of epirubicin is that it directly inserts into base pairs of DNA to interfere the transcription process and prevent the formation of mRNA. Epirubicin can inhibit the synthesis of DNA and RNA and therefore has effects on all stages of a cell cycle. Epirubicin is a cell cycle nonspecific agent. Epirubicin can affect both the cell membrane and the transport system. However, the most important site of action is nucleus. Furthermore, epirubicin can also inhibit topoisomerase II.
Epirubicin has equal to or higher anti-tumor activity comparing with adriamycin (ADM), while having lower toxic effects, especially lower toxicity on heart. It has been demonstrated that epirubicin has broad spectrum anti-tumor effects in experiments. Clinically, epirubicin is mainly used to treat leukemia, malignant lymphoma, multiple myeloma, breast cancer, soft tissue sarcoma, gastric cancer, liver cancer, colorectal cancer, ovarian cancer and the like. Comparing with adriamycin, epirubicin has relatively lower toxicity, but still results in myocardial injury and heart failure. It is shown in comparative studies that the ratio of accumulative dose causing the same degree of heart hypofunction of epirubicin to adriamycin is 2:1. Therefore, the heart function should be still carefully monitored during the treatment with epirubicin, such that the risks for heart failure can be reduced (such a heart failure even occurs several weeks later after the treatment stops and may be of no effects on the corresponding drug treatment). As to patients that are currently receiving or has received the concomitant radiotherapy for mediastinum and pericardial regions, the potential risks for heart toxicity of epirubicin may increase and may has marrow inhibition, gastrointestinal reaction such as nausea, vomiting, etc, skin reaction such as dermatitis, pigmentation, etc, and toxic side effects such as phlebitis, cellulitis, etc.